We find a surprising connection between multitask learning and robustness to neuron failures.

Learning to play a musical instrument can protect your brain from aging, building up a defense against cognitive decline that lasts a lifetime. Researchers from Canada and China discovered older adults who had spent years playing music were better at understanding speech in noisy environments, like a crowded room, compared to those who didn't play music. Their brains worked more like younger people's brains, needing less energy to focus than older non-musicians' brains had to use to make up for age-related mental declines. Playing music was found to build up a person's'cognitive reserve,' which is like a backup system in the brain. This reserve helps the brain stay efficient and work more like a younger brain, even as someone grows older.

As artificial neural networks grow in complexity, understanding their inner workings becomes increasingly challenging, which is particularly important in healthcare applications. The intrinsic evaluation metrics of autoregressive neural language models (NLMs), perplexity (PPL), can reflect how "surprised" an NLM model is at novel input. PPL has been widely used to understand the behavior of NLMs. Previous findings show that changes in PPL when masking attention layers in pre-trained transformer-based NLMs reflect linguistic anomalies associated with Alzheimer's disease dementia. Building upon this, we explore a novel bidirectional attention head ablation method that exhibits properties attributed to the concepts of cognitive and brain reserve in human brain studies, which postulate that people with more neurons in the brain and more efficient processing are more resilient to neurodegeneration. Our results show that larger GPT-2 models require a disproportionately larger share of attention heads to be masked/ablated to display degradation of similar magnitude to masking in smaller models. These results suggest that the attention mechanism in transformer models may present an analogue to the notions of cognitive and brain reserve and could potentially be used to model certain aspects of the progression of neurodegenerative disorders and aging.

Scientists say they can tell how badly your memory will fade six decades before it happens. Participants who scored poorly on mental tests at the age of eight were more likely to have thinking and memory problems by the time they reached 70. Researchers said their findings suggest subtle cognitive differences could be a marker for dementia before the symptoms appear. However, the results did not investigate whether cognitive skills in childhood are linked to the risk of developing dementia. Education and income, assessed by occupation at the age of 53, was also shown to be an indicator of how brain power declines in your 70s.

All this week, two eminent neurologists specialising in Alzheimer's are sharing cutting-edge research with Mail readers and revealing how lifestyle tweaks can help fend off the disease. Today, they show how challenging your mind and increasing your social life can help protect your brain against decay . . . You might be fan of a fiendishly complex crossword puzzle or a demon at sudoku, but even if you regularly rattle off the answers when watching University Challenge on TV or flick through the financial pages of the weekend papers, are you properly exercising your brain? Our work as specialists in Alzheimer's has taught us that simple puzzles are not enough. One fundamental factor in the fight to protect yourself against dementia -- and to slow its march if it has already started -- is the quest to build what neuroscientists call'cognitive reserve'. A healthy brain thrives on challenge, especially challenges that are personally relevant and involve many different parts of the brain at the same time. That's because our brains are designed for complexity and they are sustained by it in old age.